Image Alignment automatically compensates for camera movement between frames when capturing computational photography sequences. Even with a tripod, slight camera shake or movement can cause misalignment. This feature ensures all images in a sequence are perfectly registered before they're combined.
Image alignment is automatically performed as the first step in focus stacking, motion removal, HDR merging, long exposure, and astrophotography workflows.
You can download test images for use with SpotmaticMagic from: Google Drive
Image alignment is automatically applied in:
Configure in iOS Settings → ElectroSpotmatic → Image Alignment Algorithm:
When a frame is too misaligned to combine cleanly with the others, ElectroSpotmatic will skip it and use the remaining frames instead. This matters most for HDR: a single wildly-shifted bracket can otherwise contaminate the merged image with ghosting or content that doesn't match the rest of the scene.
If the app skips a frame, it tries other alignment methods in turn before giving up — so as long as at least one of the methods can register the frame, you get a good result.
Best for: All workflows. Replaced Vision Framework as the default in 2026.
How it works: Detects distinctive points in each frame and matches them between frames, then computes the camera motion that best lines up the matches. Picks the simplest motion that fits — pure translation, rotation + zoom, or a full perspective warp — automatically.
Advantages: GPU-accelerated end-to-end on iPhone and iPad. Handles rotation, scale, and perspective natively. Significantly faster than Vision Framework on multi-frame HDR sequences.
Limitations: Works best on scenes with plenty of detail and texture. On blurry or low-texture frames (heavily defocused shots, blank skies) the app automatically switches to a simpler method.
Best for: When you want Apple's built-in alignment directly, or as the automatic backup when another method has trouble.
Advantages: Reliable and well-tested across iOS versions. Handles intensity changes between frames gracefully — useful for HDR sequences where exposures vary.
Limitations: Best at simple camera motion (translation); can reject extreme warps that Feature-Based handles. Slower than Feature-Based on multi-frame sequences because Feature-Based runs entirely on the GPU.
Best for: Macro photography and telephoto focus stacks where the image shifts subtly with focus distance.
Advantages: Very precise on the kind of small, smooth motion you get from focus breathing. Optimized so it stays fast on tripod-stable shots.
Limitations: Slower on shots with significant movement between frames, where it has to do more work. Large camera shifts can fall outside its working range, in which case the app automatically falls back to another method.
Best for: Scenes where finding distinctive points isn't reliable — for example, very low-texture inputs.
How it works: Aligns frames by matching pixel brightness directly rather than by finding feature points.
Limitations: Like IC-LM, fast on tripod shots and slower on shots with real movement. Large camera shifts can fall outside its working range, in which case the app automatically falls back to another method.
Aligned images are cropped: This is expected — images are cropped to the area they all share after alignment.
Poor alignment results: Make sure the scene has plenty of detail and that all the images are of the same scene. On heavily blurred frames (like focus-stack shots well away from the reference frame), the app will automatically fall back to a simpler alignment method.
Alignment fails: Very featureless scenes (for example, a night sky with no stars visible) may not align well. Make sure the frames have good overlap with each other.
Alignment is slower than expected: Feature-Based runs on the GPU; if alignment is slow on a recent iPhone or iPad, your device may be falling back to a slower path. Restart the app and try again, or switch to a different alignment method in Settings.
Last updated: 2026-05-12